Degenerative valvular disease is the most common cause of valvular regurgitation in human beings. Regurgitation is typically characterized by an expanded valve annulus or by lengthened chordae tendineae. In either case, an increase in the geometry of a valve or its supporting structure causes the valve to become less effective, as it no longer fully closes when required.
Loose chordae tendineae may result, for example, from ischemic heart disease affecting the papillary muscles. The papillary muscles attach to the chordae tendineae and keep the leaflets of a valve shut. Some forms of ischemic cardiac disease cause the papillary muscles to lose their muscle tone, resulting in a loosening of the chordae tendineae. This loosening, in turn, allows the leaflets of the affected valve to prolapse, causing regurgitation.
It therefore would be desirable to provide methods and apparatus for treatment of tissue that modify the geometry and operation of a heart valve.
It would also be desirable to provide methods and apparatus that are configured to thermally treat chordae tendineae, the annulus of a valve, or valve leaflets.
It would also be desirable to further provide methods and apparatus that are configured to mechanically modify the geometry and operation of a heart valve and annulus of a valve either alone or in addition to thermal treatment.